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Various Elements (various + element)
Selected AbstractsOlfactory preference for own mother and litter in 1-day-old rabbits and its impairment by thermotaxisDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2008Jessica Serra Abstract We investigated the ability of rabbit pups to display preferences towards various elements of their postnatal environment during the stage of confinement in the nest. Subjects were submitted to a two-choice test during the first week after birth to assess if they could detect and discriminate between does, litters of pups, or nesting materials of the same developmental stage. On D1 and D7, pups were attracted to any lactating doe, litter, or nest when compared to an empty compartment. When two stimuli were opposed, pups preferred their own nest to an alien one on D1 and D7 but not their mother nor their siblings when opposed to alien does or pups. However, additional tests indicated that this lack of preference for kin conspecifics resulted from a predominant attraction to thermal cues over individual odors. Indeed, pups were strongly attracted to a warm compartment (37°C) than to a cooler one (20°C) and once thermal cues were controlled for in the testing situation, the pups were specifically attracted to odors of their own mother's hair and of their siblings. No preference was observed towards the mother's uterine secretions. In conclusion, pups can recognize olfactory cues emanating from their mother and their siblings the day after birth. The preference for nesting materials would reflect in major part the combined attraction to maternal and sibling odors present in the nest. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 542,553, 2008. [source] The influence of parent material on topsoil geochemistry in eastern EnglandEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2003B. G. Rawlins Abstract The topsoil of around 10 000 km2 in eastern England has recently been sampled intensely at 4609 sites to characterize its geochemistry. The parent materials, which include both solid geology and Quaternary sediments, range in age from Permian to Holocene. The distributions of the concentrations of major and trace elements have been characterized geostatistically, and the role of parent material on their spatial structure (anisotropy) and their spatial relationships (coregionalization) have been investigated. Analysis of variance with the sites grouped by major parent material type showed that this classi,cation accounted for 14 to 48 per cent of the variance for the various elements. Global variograms of 13 elements (Al, As, Ca, Cr, Cu, Fe, Mg, Mo, Ni, P, Pb, Ti, and U) have been computed and modelled. Eleven of the variograms seem to comprise two structures, both of which we modelled with spherical functions, one of short range, 3·5 to 9 km, and the other with a range of 15 to 23 km. The models included a nugget variance, which varied from 27 per cent (for As, Fe, and Mg) to 63 per cent (for P) of the total. The long-range structures are related to the separations of the major parent materials. The variograms of several elements showed appreciable anisotropy, most notably that of Mg. Anisotropy is evident at short ranges of less than 5 km. This accords with the geological structure of the beds which dip from west to east so that their outcrops are elongated from north to south. A linear model of coregionalization ,tted to the data emphasized several important geochemical associations, which we interpret. Elements commonly associated with clay minerals (Mg, Al) and the clay size fraction (Ti) are dominated by the long-range structure of the coregionalization, whilst several trace elements (As, Cr, Ni and U) are spatially correlated with Fe over short distances, through adsorption of the former on the surfaces of Fe oxyhydroxides. The topsoil around large urban areas is enriched in lead, but it is not clear whether anthropogenic sources are responsible for this metal's anomalous spatial relationships with other elements. Crown copyright © 2003. Reproduced with the permission of Her Majesty's Stationery Of,ce. Published by John Wiley & Sons, Ltd. [source] On the estimation of fatigue life in notches differentiating the phases of crack initiation and propagationFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2010J. VÁZQUEZ ABSTRACT Over the last three decades, a variety of models have been developed in order to predict the life of components under fatigue. Some of the models are based on the definition of the fatigue process as a combination of the phases of crack initiation and crack propagation, considering component life as the sum of the duration of each phase. Other models consider only one of the phases; some consider only initiation while others only propagation, though in this case, from cracks with lengths in the order of the microstructural dimensions. This article will carry out a comparative analysis of the methods that consider life as the sum of the duration of both phases. In this same line, it proposes yet another method, which simulates crack growth according to damage theories. In analysing the behaviour of each model, this paper will describe various elements: the prediction that each of them produces regarding notched specimens submitted to testing, the advantages and inconveniences of each, and lastly, the possibilities of applying each of the models to more realistic geometries. [source] Cadmium phytoextraction capacity in eight C3 herbage grass speciesGRASSLAND SCIENCE, Issue 1 2008Shamima Sabreen Abstract Grasses are excellent candidates for phytoremediation because of their high biomass production, high adaptability and low management cost. This study assesses interspecific variation of cadmium (Cd) phytoextraction capabilities in eight C3 grass species. Populations of 30-day-old C3 grass species , namely, Agrostis alba, Anthoxanthum odoratum, Dactylis glomerata, Festuca arundinacea, Festuca pratensis, Lolium multiflorum, Lolium perenne and Poa pratensis, were grown hydroponically for 15 days with different concentrations of Cd (0, 5, 10 and 50 µM). For each species, shoot biomass, the proportion of growth inhibition (GI, %), shoot Cd concentration and accumulation, shoot nutrient uptake, and the proportion of uptake inhibition (UI, %) of nutrient minerals were evaluated. Effects of Cd application included stunted growth. The GI increased from 5% to 70% with an increase in Cd concentrations. For all Cd treatments, L. multiflorum showed the highest shoot dry biomass. Shoot Cd concentrations negatively affected mineral nutrient uptake. The highest Cd treatment caused UI of various elements of 37,95%. Under 50-µM Cd treatment, Cd accumulation varied by 20 times among species, and L. multiflorum showed the highest Cd accumulation (116.46 µg plant,1). Our results indicate that L. multiflorum exhibited high degrees of both Cd tolerance and Cd phytoextraction capacity among grass species. [source] Comprehensive elements of a physiotherapy exercise programme in haemophilia , a global perspectiveHAEMOPHILIA, Issue 2010G. BLAMEY Summary., Exercise programmes for people with haemophilia are usually designed and implemented to help manage the recovery after a haemarthrosis or a muscle bleed, or as a tool to help prevent bleeding episodes from occurring. In this article, we have identified individual components of exercise that are often applied as separate entities, but may also need to be implemented in concert for optimized impact. Although it may be necessary on occasion to bias an exercise programme towards one component over the others, it is important to recognize that the various elements of exercise are not mutually exclusive. Decreased flexibility, strength and proprioception, will result in an impairment of balance and a loss of function. Programme design should whenever possible be guided by proven methodology in terms of how each component is incorporated, and more specifically how long to perform the exercise for and how many repetitions should be performed. We recognize, however, that this is not always possible and that there is significant value in drawing from the experience of clinicians with specialized training in the management of haemophilia. In this study, both perspectives are presented, providing reference-based reviews of the mechanics of the various elements of exercise as well as the expert opinions of the authors. Research that has been completed using patients with conditions other than haemophilia may or may not have a direct application with the bleeding disorders population, but the programme design based on principles of tissue healing in addition to disease specific knowledge should be encouraged. [source] Territorial song and song neighbourhoods in the Scarlet Rosefinch Carpodacus erythrinusJOURNAL OF AVIAN BIOLOGY, Issue 3 2000Jochen Martens Throughout the range of the Scarlet Rosefinch, its territorial song consists of 3,9 (usually 4,5) elements, of which there are 5 different types. The differences lie in the way the pitch of the element changes in time (frequency "slope") and the width of the frequency band. Within a given type of song, the various elements can be present in almost any combination. Therefore, so many song types can be formed that the songs in even small parts of the species' area are clearly distinct from one another. Despite this capacity for variation, however, by chance identical songs may be sung in widely separated parts of the area, in some cases by different subspecies. The species has not developed large-scale dialects or regiolects based on a song tradition acquired during an early imprinting phase. Scarlet Rosefinches tend to breed in small colonies, groups of up to about 15 pairs characterized by the same type of song (song neighbourhoods, formed by the development of a microlect). Microlects develop by a founder effect. When males, near one-year old or older, join one another to form isolated colonies after arrival in the breeding region, they adopt ("learn") the song type that will eventually characterize the colony from the first male to arrive at the site. After the colony has been founded, in most cases each male uses only one type of song during a breeding season, with practically no variation of the temporal and frequency parameters. Singing the same type of song, the members of a colony accept one another sufficiently to allow the breeding territories to be closely packed. It appears that a long-lasting capacity for acoustic learning, in combination with colony-like breeding and great ecological flexibility, has allowed the Scarlet Rosefinch to become the most successful species of the genus Carpodacus. [source] Cost Comparison of Catheter Ablation and Medical Therapy in Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2007F.R.C.P.C., YAARIV KHAYKIN M.D. Introduction: There is emerging evidence for clinical superiority of catheter ablation over rate and rhythm control strategies in paroxysmal atrial fibrillation (PAF). The objective of this study was to compare costs related to medical therapy versus catheter ablation for PAF in Ontario (Canada). Methods: Costs related to medical therapy in the analysis included the cost of anticoagulation, rate and rhythm control medications, noninvasive testing, physician follow-up visits, and hospital admissions, as well as the cost of complications related to this management strategy. Costs related to catheter ablation were assumed to include the cost of the ablation tools (electroanatomic mapping or intracardiac echocardiography-guided pulmonary vein ablation), hospital and physician billings, and costs related to periprocedural medical care and complications. Costs related to these various elements were obtained from the Canadian Registry of Atrial Fibrillation (CARAF), government fee schedules, and published data. Sensitivity analyses looking at a range of initial success rates (50,75%) and late attrition rates (1,5%), prevalence of congestive heart failure (CHF) (20,60%), as well as discounting varying from 3% to 5% per year were performed. Results: The cost of catheter ablation ranged from $16,278 to $21,294, with an annual cost of $1,597 to $2,132. The annual cost of medical therapy ranged from $4,176 to $5,060. Costs of ongoing medical therapy and catheter ablation for PAF equalized at 3.2,8.4 years of follow-up. Conclusion: Catheter ablation is a fiscally sensible alternative to medical therapy in PAF with cost equivalence after 4 years. [source] A Human Oral-throat Cast Integrated with a Twin-stage Impinger for Evaluation of Dry Powder InhalersJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2000T. SRICHANA The aim of this study was to investigate the applicability of replacing the glass throat from a twin-stage impinger (TSI) with a human oral-throat cast. Monodisperse aerosols were used to calibrate the human oral cast-TSI at 60 L min,1 and cut-off in particle size was compared with that of the TSI described in the British Pharmacopoeia which employs a glass throat. The amount of salbutamol sulphate (and lactose) delivered by the Cyclohaler depositing on various elements of the in-vitro model were determined. The calibration of the model containing a human oral-throat cast at 60 L min,1 gave a particle size cut-off of 5.2 ,m which was less than that of the TSI (6.3 ,m). The oral-throat cast trapped more drug than the glass throat model with a formulation that employed the larger carrier (63,90 ,m; P<0.05) while it trapped a lesser amount of drug with those filled with the lower size carrier (Lactochem, micronised lactose). The greater amount of lactose in the formulation that employed the larger-sized carrier (63,90 ,m) was deposited closer to the inlet of the oral-throat cast than to the inlet of the glass throat model. Replacement of the glass throat in the TSI by the human oral-throat cast, leads to a change in deposition efficiency, with the cast having a higher filter efficiency and hence more aerosol particles being captured before their entry into the TSI. This should be investigated further to determine whether such a model might provide a more realistic assessment of the in-vivo characteristics of an aerosol in comparison with the TSI currently being employed, which utilises the glass throat as the portal of entry. [source] Managed socialization: how smart companies leverage global knowledgeKNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 3 2007Deependra Moitra Driven by economic and market forces, the last 2 decades have witnessed a phenomenal acceleration in the pace of globalization. Today, globalization, and particularly globalization of knowledge work, has emerged as a business necessity. In their quest for competitiveness, more and more companies are leveraging global resources by distributing knowledge work across borders and essentially establishing around-the-clock innovation engines. Yet, managing knowledge,the most valuable resource of the new economy enterprises,remains to be a formidable business challenge to deal with. This challenge assumes even greater complexity in the context of globalization, characterized by distance, language barriers, cultural diversity, and a host of other socio-political factors. Whilst there have been considerable developments in the discipline of knowledge management, much of that does not quite alleviate the struggle companies face in effectively harnessing global knowledge. Specifically, while much progress has been made in managing explicit knowledge, firms find it hard to capture and leverage the tacit knowledge, which holds the key to knowledge-based competition. This paper argues that this inability to capitalize on the tacit knowledge stems from a missing ,social' dimension in the design of knowledge management strategies, which when addressed leads to unleashing the valuable tacit knowledge. Drawing on real-world research spanning 12 leading companies, in this paper we discuss Managed Socialization,the most vital management process for harnessing global knowledge. We argue that only by instituting managed socialization firms can truly succeed in leveraging global knowledge. Toward that, we describe the various elements that constitute managed socialization and based on case studies distil actionable insights that firms can capitalize on to fuel their quest for global dominance. Copyright © 2007 John Wiley & Sons, Ltd. [source] The role of mass spectrometry to study the Oklo,Bangombé natural reactors,MASS SPECTROMETRY REVIEWS, Issue 5 2007J.R. De Laeter Abstract The discovery of the existence of chain reactions at the Oklo natural reactors in Gabon, Central Africa in 1972 was a triumph for the accuracy of mass spectrometric measurements, in that a 0.5% anomaly in the 235U/238U ratio of certain U ore samples indicated a depletion in 235U. Mass spectrometric techniques thereafter played a dominant role in determining the nuclear parameters of the reactor zones themselves, and in deciphering the geochemical characteristics of various elements in the U-rich ore and in the surrounding rock strata. The variations in the isotopic composition of a large number of elements, caused by a combination of nuclear fission, neutron capture and radioactive decay, provide a powerful tool for investigating this unique geological environment. Mass spectrometry can be used to measure the present-day elemental and isotopic abundances of numerous elements, so as to decipher the past history of the reactors and examine the retentivity/mobility of these elements. Many of the fission products have a radioactive decay history that have been used to date the age and duration of the reactor zones, and to provide insight into their nuclear and geochemical behavior as a function of time. The Oklo fission reactors and their near neighbor at Bangombé, some 30 km to the south-east of Oklo, are unique in that not only did they become critical some 2,×,109 years ago, but also the deposits have been preserved over this period of geological time. The long-term geochemical behavior of actinides and fission products have been extensively studied by a variety of mass spectrometric techniques over the past 30 years to provide us with significant information on the mobility/retentivity of this material in a natural geological repository. The Oklo,Bangombé natural reactors are therefore geological analogs that can be evaluated in terms of possible radioactive waste containment sites. As more reactor zones were discovered, it was realized that they could be classified into two groups according to their burial depth in the Oklo mine-site. Reactor Zones 10, 13, and 16 were buried more deeply, and were therefore less weathered than the other zones. The less-weathered zones are of great importance in mobility/retentivity studies and therefore to the question of radioactive waste containment. Isotopic studies of these natural reactors are also of value in physics to examine possible variations in fundamental constants over the past 2 billion years. © 2007 Wiley Periodicals, Inc., Mass Spec Rev 26:683,712, 2007 [source] Subscriber data management in IMS networksBELL LABS TECHNICAL JOURNAL, Issue 4 2006Daniel F. Lieuwen Next-generation communication services will be driven by increasingly rich and distributed subscriber information. Current wireless networks have evolved such that subscriber information now resides in various elements (e.g., home location register [HLR], prepay, voice mail, short message, and location determination systems). Convergence with the Internet promises significantly more personal information, such as presence, calendars, address books, buddy lists, pictures, and video. The home subscriber server (HSS) in the IP Multimedia Subsystem (IMS) architecture provides centralized storage for subscriber data. However, some application servers will also have their own subscriber data. As the quantity and variety of applications grow, it will become increasingly useful to provide unified views of subscriber data both within a network and across networks. The Lucent DatagridÔ software provides a telecom-targeted data integration capability, so that applications can use a logical "single-point-of-access" for user profile information inside a service provider's network. © 2006 Lucent Technologies Inc. [source] | |||||||||||||